Federal investigators on special counsel Robert Mueller’s team are probing whether President Donald Trump tried to hide the nature of Donald Trump Jr.’s meeting with a Kremlin-linked lawyer in crafting his son’s initial statement on the meeting, NBC News reported Monday evening, citing three unnamed sources familiar with the matter.

Investigators want to know what Trump knew about the meeting before crafting the statement and whether he knowingly issued an incorrect statement, sources told NBC News.

In June 2016, Donald Trump Jr., along with Jared Kushner and Paul Manafort, met with a Kremlin-linked lawyer after being promised incriminating information on Hillary Clinton as part of a Russian government effort to help Trump’s campaign. The meeting came to light in July 2017 in a New York Times report.

Though Trump Jr. eventually acknowledged that the meeting was pitched as an opportunity to gain damaging information on his father’s opponent, his initial statement claimed that the meeting was largely about Russian adoption.

The President reportedly played a large role in crafting that initial misleading statement, aboard Air Force One on his way back from a trip to Europe. Mueller’s team now reportedly wants to know how much Trump knew when he helped write that misleading statement.

Ty Cobb, a spokesman for the legal team representing the President on Russia matters, told NBC News that he assumes “the statement issued after the G20 is of interest, but I’m not aware of any crime associated with that. It was true at the time it was written and true now.” He added that the President’s involvement in writing the statement was “minimal.”